Partial substitution of anthracite for coke breeze in iron ore sintering

Qiang Zhong,Zhiwei Peng,Guanghui Li,Tao Jiang,Chen Liu,Mingjun Rao,Xin Zhang

doi:10.1038/s41598-021-80992-4

Abstract

In the sintering of iron ores, the partial substitution of anthracite for coke breeze has been considered to be an effective way of reducing pollutant emissions and production cost. In this study, the basic characteristics of anthracite and coke breeze were compared and the sintering performance at different substitution ratios of anthracite for coke breeze was investigated. The porosity of anthracite is lower than that of coke breeze, but its density and combustion reactivity are higher. The substitution of anthracite for coke breeze has no influence on the granulation effect of the sintering blend. As the anthracite proportion increased, the sintering speed and productivity increased and the sintering yield and tumbler index decreased. As the substitution ratio increased from 0 to 60%, the melting temperature duration and the melt quantity index decreased from 2.59 to 2.03 min and from 3218.28 to 2405.75 °C·min, respectively, leading to insufficient sintering mineralization and bad sintering indexes. For an anthracite substitution ratio of 40%, the sintering speed, sintering productivity, sintering yield and tumbler index were 22.34 mm min−1, 1.49 t·(m2 h)−1, 71.65% and 63.59%, respectively, which entirely satisfies the production requirements. Furthermore, hematite (Fe2O3), calcium ferrite (CaO–Fe2O3), and compound calcium ferrite (CaO–SiO2–Fe2O3) were the major mineral phases, which were embedded with an interwoven structure.

Highlights

In the sintering of iron ores, the partial substitution of anthracite for coke breeze has been considered to be an effective way of reducing pollutant emissions and production cost
This study focused on determining the basic physical and combustion characteristics of anthracite and the differences between the characteristics of anthracite and those of coke breeze
The ignition temperature refers to the start of a sudden decrease in fuel weight; the burnout temperature represents the point at which combustion is complete; and the τ is the time needed for the coke breeze and anthracite combustion to progress from ignition to burnout

Summary

Introduction

In the sintering of iron ores, the partial substitution of anthracite for coke breeze has been considered to be an effective way of reducing pollutant emissions and production cost. Hydrogen-based gaseous fuel has used as another substitution fuel It can reduce the C O2 emission and improve energy efficiency, but need extra energy efficiency, which increases the cost in iron ore s intering[15,16]. Based on the above issues, anthracite has become the main substituting fuel for coke breeze in iron ore sintering due to its reasonable price[19,20]. When this substitution is made, the particle size of the anthracite needs to be Scientific Reports | (2021) 11:1540

Methods

Results

Conclusion